Resonant Inelastic X-Ray Scattering Reveals Hidden Local Transitions of the Aqueous OH Radical.

Resonant inelastic x-ray scattering (RIXS) provides remarkable opportunities to interrogate ultrafast dynamics in liquids. Here we use RIXS to study the fundamentally and practically important hydroxyl radical in liquid water, OH(aq). Impulsive ionization of pure liquid water produced a short-lived population of OH(aq), which was probed using femtosecond x-rays from an x-ray free-electron laser. We find that RIXS reveals localized electronic transitions that are masked in the ultraviolet absorption spectrum by strong charge-transfer transitions-thus providing a means to investigate the evolving electronic structure and reactivity of the hydroxyl radical in aqueous and heterogeneous environments. First-principles calculations provide interpretation of the main spectral features.

Observation of the fastest chemical processes in the radiolysis of water.

Elementary processes associated with ionization of liquid water provide a framework for understanding radiation-matter interactions in chemistry and biology. Although numerous studies have been conducted on the dynamics of the hydrated electron, its partner arising from ionization of liquid water, H2O+, remains elusive. We used tunable femtosecond soft x-ray pulses from an x-ray free electron laser to reveal the dynamics of the valence hole created by strong-field ionization and to track the primary proton transfer reaction giving rise to the formation of OH. The isolated resonance associated with the valence hole (H2O+/OH) enabled straightforward detection. Molecular dynamics simulations revealed that the x-ray spectra are sensitive to structural dynamics at the ionization site. We found signatures of hydrated-electron dynamics in the x-ray spectrum.

[Clinical characteristics and survival analysis of de novo grade 3 or transformed follicular lymphoma patients].

Objective: To evaluate the clinical characteristics and survival outcomes of patients with de novo grade 3 or transformed follicular lymphoma (FL). Methods: Fifty-two patients treated at Peking University Cancer Hospital between January 2009 and September 2017 were assessed, including 28 patients with FL 3A grade, 13 patients with FL 3B grade, 11 patients with transformed FL. Baseline characteristics, survival and prognostic factors were analyzed. Results: ① Twenty-six male and 26 female patients were enrolled, including 28 patients with FL 3A grade, 13 patients with FL 3B grade, 11 patients with transformed FL. ②The 3-year progression-free survival (PFS) and overall survival (OS) for the entire cohort were 56.0% and 80.6%, respectively. Patients with international prognostic index (IPI) score 0-1 demonstrated significantly better 3-year PFS (80.3% vs 20.1%; t=18.902, P<0.001) and OS (95.7% vs 57.0%; t=10.406, P<0.001) than patients with IPI score 2-3. Three-year PFS (94.1% vs 37.2% vs 25.2%; P=0.002) and OS (100.0% vs 76.0% vs 59.8%; P=0.020) were also significantly different among patients with FLIPI 1 score 0-1, 2, ≥3. FLIPI 2 score was also identified as a prognostic factor for 3-year PFS (68.4%, 0, 0; P=0.001) and OS(87.5%, 76.2%, 0; P=0.003). ③Multivariate analysis indicated a significant association of PFS (HR=3.536, P=0.015) and OS (HR=15.713, P=0.015) with IPI. FLIPI 2 was associated with OS (score 0-1, HR=0.078, P=0.007; score 2, HR=0.080, P=0.022). Conclusion: De novo grade 3 or transformed FL might be a group of curable disease with current treatment strategies. IPI is still a prognostic tool in this scenario.

[Prognostic significance of (18)F-fluorodeoxyglucose positron emission tomography in patients with diffuse large B cell lymphoma undergoing autologous stem cell transplantation].

Objective: To evaluate the prognostic value of (18)F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) in patients with diffuse large B cell lymphoma (DLBCL) undergoing autologous hematopoietic stem cell transplantation (auto-HSCT). Methods: Forty-eight patients with DLBCL treated at Peking University Cancer Hospital between November 2010 and December 2014 were assessed. All patients underwent PET/CT scanning prior to or after auto-HSCT. Correlation analysis was done based upon patients characteristics, PET/CT scan results and survival. Results: ①Among 48 patients, 27 was male, 21 female, median age was 43 (17-59) years old. ② Patients with negative pre-auto-HSCT PET/CT assessment demonstrated significantly better 3-year progression free survival (PFS) (87.1% vs 53.3%, χ(2)=7.02, P=0.019) and overall survival (OS) (90.3% vs 60.0%, χ(2)=6.51,P=0.022) than patients with positive pre-auto-HSCT PET/CT assessment. Three-year PFS (94.1% vs 30.0%, χ(2)=22.75, P=0.001) and OS (97.1% vs 40.0%, χ(2)=21.09, P=0.002) were also significantly different between patients with negative and positive post-auto-HSCT PET/CT assessment. ③ Multivariate analysis indicated a significant association of PFS (HR=13.176, P=0.005) and OS (HR=20.221, P=0.007) with post-auto-HSCT PET/CT assessment. Number of prior treatment regimens was associated with PFS (HR=10.039, P=0.040). ④ Harrell's C index revealed that the value of combined use of number of prior treatment regimens and post-auto-HSCT PET/CT assessment was superior to either one used alone in PFS (Harrell's C values were 0.976, 0.869 and 0.927 in combined use, number of prior treatment regimens and post-auto-HSCT PET/CT assessment, respectively), and the combined use of ECOG performance status and post-auto-HSCT PET/CT assessment significantly increased the Harrell's C index in OS (Harrell's C values were 0.973, 0.711 and 0.919 in combined use, ECOG performance status and post-auto-HSCT PET/CT assessment, respectively). Conclusions: Post-auto-HSCT PET/CT assessment is the main predictor of outcomes in DLBCL patients receiving auto-HSCT. Combined use of post-auto-HSCT PET/CT assessment and number of prior treatment regimens and ECOG performance status is a better prognostic tool in patients with DLBCL undergoing transplantation.

[Clinical features, diagnosis, treatment, and prognosis of 99 cases with primary intestinal lymphoma].

Objective: To investigate the clinical features, diagnosis, treatment and prognosis of primary intestinal lymphoma (PIL) . Methods: The characteristics, diagnosis, treatment methods, and follow-up outcomes of 99 PIL patients, diagnosed in Peking university cancer hospital between Nov.1,1995 and Nov. 30, 2013. Results: There were 65 males and 34 females with a median age of 50 years. The majority of clinical manifestation were non-specific gastrointestinal symptoms, 67.68% of cases presented abdominal pain, 26.26% with acute abdomen. The most common primary sites of ileum and ileocecus were identified in 21 cases, respectively. The positive rate of endoscopic was only 24.24%, and 69 cases were diagnosed by operation. 71 patients (71.72%) were stageⅠ-Ⅱand 28 patients (28.28%) were stage Ⅳ. Hodgkin's lymphoma was not found in all patients. Of the 99 cases, 77 were B-cell origin (77.78%) and 22 were T-cell origin. 55 cases (55.56%) were diagnosed with diffuse large B cell lymphoma (DLBCL) . 60 cases presented IPI score 0-1 point. The median overall survival (OS) was 100.0 months, and 5 year overall survival (5y-OS) was 53.5%. By multiple-factors analysis, T-cell origin lymphoma was significantly correlated with poor prognosis (P<0.05) . There was no difference of the median OS between the patients with operation and chemotherapy alone (79.0 vs 123.0 months, P=0.616) . Conclusion: PIL is commonly seen in males. Abdominal pain is the most common clinical manifestations and the most primary sites are ileum and ileocecus. The diagnosis value of the endoscopic is limited. DLBCL is the most common pathologic type of PIL. T-cell origin lymphoma is an independent prognostic factor for PIL. Surgery is still commonly used in the diagnosis and treatment of PIL, and the operation do not increase the risk of death of patients with PIL.

[Efficacy and survival analysis of DICE regimen for 97 patients with relapsed or refractory Non-Hodgkin's lymphoma].

Objective: To investigate the efficacy and survival of the DICE regimen (cisplatin, ifosfamide, etoposide, dexamethasone) for relapsed and refractory NHL. Methods: Clinical data of 97 relapsed and refractory NHL patients treated with DICE regimen in Peking University Cancer Hospital between Sep 1. 2008 and Dec 31. 2013 were retrospectively analyzed, and then we evaluate the efficacy and safety of DICE regimen. Results: ① There were 64 males and 33 females with a median age of 49 years. The most common pathological type was DLBCL (73.20%). There were 35 B-NHL patients used rituximab combined with DICE. Finally, a total of 26 patients underwent autologous stem cell transplantation (auto-HSCT) after the salvage chemotherapy. ② The overall response rate (ORR) was 47.42%, the complete response (CR) rate was 22.68%. The ORR of the relapsed/progressive group was higher than the refractory group [67.57% (25/37) vs 35.00% (21/60), χ2= 9.736, P=0.002]. ③The median follow-up of these 97 patients was 15.0 months (1.5-80.0 months). The expected median progression-free survival (PFS) and overall survival (OS) was 12.0 (95% CI 5.0-19.0) months, 26.0 (95% CI 6.0-45.9) months. ④There was no difference between the auto-HSCT group and no auto-HSCT group in the median OS [41.0 (95%CI 8.9-73.1) vs 22.0 (95%CI 8.5-35.5) months, P=0.361]. The patients who achieved CR and PR after DICE regimen had longer OS than those patients who in stable or progressive disease (56.0 vs 18.5 months, P <0.001). Patients who used DICE combined with rituximab had longer OS than patients who only used DICE regimen (51.5 vs 28.5 months, P=0.041). The multiple-factor analysis showed that the efficacy of DICE was an independent prognostic factor of OS [HR=4.24 (95%CI 2.12-8.50), P<0.001 ]. ⑤ The major adverse events included neutropenia (84.54% ) , thrombocytopenia (41.24% ), anemia (68.04%), and nausea/vomiting (65.98%), 14 patients (14.43%) had liver function abnormality, 1 patient had acute renal function injury during the treatment period. There was no chemotherapy-related death occurred. Conclusion: The DICE regimen is effective in refractory and relapsed NHL, and DICE is safe and well-tolerated. The high response rate of DICE regimen may correlate with good prognosis. For the B-NHL patients who used DICE combined with rituximab had longer OS than those patients who used DICE regimen only.